India test-fired three medium-range, surface-to-air missiles on Monday from its main testing center in Chandipur in Orissa, a defense ministry spokesman said.

The missiles were fired out into the ocean over a span of 17 minutes from the testing center, said the spokesman, on condition of anonymity in accordance with official policy.

He described the tests as routine.

The missile, Akash, has a range of 25 kilometers, carries a 60-kg payload and is designed to hit several incoming aircraft simultaneously. It was developed by the Defense Research and Development Organization.

The missile test was conducted on the same day India and Pakistan signed an agreement in Islamabad formalizing their long-standing practice of notifying each other of plans for ballistic missile tests.

It was not immediately clear whether India had informed Pakistan ahead of Monday's tests. Both countries regularly test-fire missiles, but normally give each other prior notice for long-range launches.

The army has been testing Akash since at least three years. Defense ministry officials said the tests are intended to check the flight parameters of the missiles, which are still being refined.

India's missile arsenal also includes the short-range Prithvi missile, the anti-tank Nag missile, the short-range surface-to-air Trishul missile, and the supersonic Brahmos missile.